Temperatures have plummeted across the UK, as snow showers and icy conditions swept the country, closing schools and disrupting travel.

Scotland, northern England and Wales The Met Office has issued four yellow warnings for snow and ice in Scotland, northern England and Wales. Wintry showers were predicted across Wales, northern and western England into Wednesday morning, as well as over north-west Scotland and Northern Ireland from Tuesday afternoon.

Up to 10cm of snow was expected to fall at higher levels in Scotland and Wales, with 1-2cm expected on lower ground. Temperatures dropped to around -7C (19F) across the Highlands overnight.

Highland council closed 13 primary schools and nurseries on Tuesday morning because of the weather, while pupils across north Wales were also told to remain at home as cars became trapped in snowdrifts along the A487, the main road that borders Snowdonia national park near Machynlleth, Powys.

There had already been significant snowfall in parts of the Highlands and the snow gates on the A939, the Old Military Road in the heart of the Cairngorms national park, were closed between Cock Bridge and Tomintoul from Monday afternoon.

Despite overnight snowfall, flights to and from Aberdeen airport have been operating as usual, although the airport cautioned travellers to leave extra time on their way to the terminal and take care on the roads.

In the far north of Scotland, a motorist was issued with a fixed penalty notice after being caught driving a snow-covered car with only a small square of windscreen cleared. Police Scotland released photographs of the car, which was stopped on the A9 at Thurso, Caithness, as a warning to other drivers.

This driver was issued with a fixed penalty notice. Photograph: Police Scotland/PA

A police spokesman said: “Winter has been biting for most of us this week, which means it is more important than ever that your vehicle is suitably prepared for the roads. Unfortunately not everyone follows this advice. It is important before you set off to make sure your windows are clean, properly demisted and clear of all snow and ice before you drive.”

A further warning, for the south-east of England, the Midlands, and East Anglia, continues into Wednesday, and the Met Office expects rain and snow to move in from the south-west, moving across England and Wales, on Thursday and into Friday.

Paul Gundersen, the Met Office’s chief meteorologist, said: “As the moist air from a weather system bringing storms to France clashes with the cold air sitting over the UK, it brings the chance of wintry showers and snow disruption to most parts.

“It’s not possible at this stage to be certain where exactly will see the worst impacts of any snow, but people need to be prepared for the possibility of disruption and make sure they check the forecast regularly.

“Areas of higher ground are most likely to see significant snowfall, so it’s particularly important to take extra care when planning and travelling in those places.”